Then search again for Spire and install it, we recommend to use WiFi before installing Spire as it will download more than 100 MB to download some important files directly from Apple Servers

Here’s What Chpwn described Spire on his blog :

However, Spire is not a complete solution. Apple still requires authorization to use Siri, so information from an iPhone 4S is still required. To insert this information, Spire allows you to enter your own proxy server address. I’ve put up a list of my ideas on how you might get access to a proxy; hopefully you can figure something out.

There’s any number of ways for you to get a proxy that will help you connect Siri to Apple. Here’s a few of my ideas:

westbaer’s SiriProxy fork

Own an iPhone 4S too: Maybe you already own an iPhone 4S, and just want Siri on another device of yours. This is simple; you can just use the above proxy yourself.

Find a friend: Maybe your friend has an iPhone 4S and will let you use their authentication tokens (maybe in exchange for some cool SiriProxy plugins). Then, you can share the authentication. Or, maybe you gave your relative your old iPhone when you got your iPhone 4S: now you can share your token and give them Siri.

Pay up: It’s very likely that soon we will see for-pay services online to rent you some space on a Siri proxy, attached to one of their iPhone 4S devices. I haven’t seen anything like this yet, but I’ll keep my eye out, and I would encourage anyone who is interested to set something like this up.

And now for something completely different: As I suggested earlier, you might be able to replace Siri entirely. A simple method might be to use Google Chrome’s speech “API” hooked up to some code to decode the Siri requests and parse Google’s result. Or, someone could hook it up to some logic backends like many of the clones available on Android: the possibilities are endless.

Finally you MUST have jailbroken device on iOS 5.x, you can follow our step by step guide to jailbreak iPhone, iPod or iPad – Click Here for 5.0.1 or Click Here for iOS 5.0.